In recent years there has been a tremendous growth in the number of applications where it is desirable to be able to receive electromagnetic waves having frequencies in the radio frequency range, and particularly in the range of ten's of gigahertz (i.e. having wavelengths of millimeters, called mm-wave frequencies). Such applications include local multipoint distribution systems (LMDS), microwave video on demand systems (MVDS), collision avoidance radar, wireless local area networks (WLANs) and others. This trend is further driven by increasing frequency spectrum congestion at lower (microwave) frequencies, and the desire to have global communications with ever increasing data rates. For mm-wavelength receiver technology to be successful in the market place, it is important that acceptable performance is achieved while, at the same time, component size and cost is minimised. This is so for all components of such receivers including receiver front end components which generally receive electromagnetic wave signals from, for example, an antenna and process these signals before passing them to further receiver components.